Not necessarily it’s just specifying that your backend application should be aware if allowing header based authentication. Some applications also you to specify incoming sources for those headers.
I don’t think we will remove the feature, but OAuth/OIDC will likely be the most common path of integration in the near future.
There hasn’t really been a request for this before, you could likely do it right now with some work in the reverse proxy, but we haven’t tested it.
If there’s a desire we could definitely look in to it though.